In medical settings, a biological fluid or medicament may be withdrawn from a subject or provided to a subject via a fluid handling system. For example, apheresis machines are generally configured to separate blood extracted from a subject into its constituent components (e.g., red blood cells, platelets, plasma, etc.). The blood or blood components may then be routed via a fluid handling system into different collection bags. In some cases, fluids flowing through such a fluid handling system may be divided into separate streams using a multi-lumen tube (e.g., a tube having multiple fluid paths), each lumen configured to carry a direct fluid or mixture. For example, a multi-lumen tube may be used in an apheresis system to transport whole blood or separated blood components (e.g., platelets, plasma, etc.) between the various portions of the system (e.g., a pump, a cassette, a flexible bag, a centrifuge or other blood separation mechanism, etc.).
A coupler may be used to convert a multi-lumen tube into multiple single-lumen tubes or vice-versa. For example, an adapter bushing may be inserted into the end of the multi-lumen tube to couple one of the lumens of the tube to a single-lumen tube. However, such an inserted member also substantially reduces the cross-section area of the lumen. In an apheresis or other blood-handling system, this may lead to increased hemolysis, which is a breaking or fracturing of red blood cells. Overmolded connectors may also be utilized, but can be relatively expensive components. Further, a multi-lumen tubing held in place with pins during the overmolding process can result in damage being caused to the relatively thin lumen walls of the multi-lumen tube.